The historical and continuing exponential growth in processor capability continues to provide the parallel growth in supercomputer and datacenter capacity. Technological requirements to continue this growth include high speed interconnects to access memory and to link the thousands of chips in a large machine. This presentation describes a body of work in silicon photonic transmitter technology that provides the chip-to-chip optical interconnect bandwidth for future multiprocessors. The silicon photonic technology demonstrated is, to our knowledge, the lowest power and lowest voltage external optical modulator of any kind in the world. Compatibility with current and proposed low voltage signaling is demonstrated. Intimate integration with CMOS technology is obtained in monolithic and two dimensional integration schemes. Additionally, the high volume manufacturing impacts, on what heretofore had been only piece part demonstrations, is quantified. Finally, the prospect of geographically separated data center virtualization is supported with the demonstration and theory of the long haul capability of silicon photonic microdisk modulators.